Improvement in tube-coupling steam-boilers



4 P. J. BRENNAN & Q. M. QUIGG. improvement in T-ub e-Cduplings forsteam-Boilersr No. 131,390;

Patented Sep.17, 1872.

UNITED STATES ATEN Q PATRICK J. BRENNAN AND QUENTIN M. QUIGG, or NEwYORK, N. Y, SAID QUIGG AssIeNs HIS RIGHT TO sAID BRENNAN.

IMPROVEMENT IN TUBE-COUPLING STEAM-BOILERS.

' Specification forming pm of Letters Patent No. 131,390, datedSeptember 17, 1872.

To all whom it may concern:

Be it known that we, PATRICK J. BRENNAN and QUINTIN M. QUIGG' 'Of thecity, county, and State of New York, have invented certain new anduseful Improvements in Sectional Steam-Boilers and we do hereby declarethat the-following is a full, clear, and exact description of the same,reference being had to the accompanying drawing making part of thisspecification.

This invention relates to that kind of sectional boiler which isconstructed of tubes with the water inside the same. In such boilers thetubes are often arranged in an inclined position, with the endsconnected through and by means of small box-shaped castings. By thisplan there are usually three or more joints at each end of each tube, inorder to secure the castings to the tubes and to each other in suchmanner as to provide communication for the steam and water. These jointsare liable to leak, and must all be broken when it is desired to renewan injured tube. Our invention consists of a connecting-couplingscrewing both into the tube-head and onto the tube, and arranged so thatit may be operated with an in- ;idedwrench through a hand-hole in thetube- In the drawing, Figure 1 represents a front elevation of ourimproved boiler. Fig. 2 is a longitudinal and vertical section of thesame.

same, The ends of the tubes are secured,

a manner hereafter described, in large hollow slabs B B, calledtube-heads. The products of combustion from the furnace O are preferablyconducted between the tubes up near the front tube-head B, and thencedown and.

up between the tubes, and between properlyconstructed deflecting-plates,to the rear of the boiler; thence down along the back tube-head B, andunderneath it to the rear of the same; thence through fire-tubes D D,Fig. 4, arranged within the water-tubes, and more particularly;described hereafter to the front connection E;

and thence, in front of the tube-head B, to the chimney F. In thedrawing but one deflecting-plate, G, is shown; but more can be employedin a well-known manner. H is a chamber for the reception of ashes andsoot that may be carried over the bridge-wall or deflecting plates. 0. aare bearers supporting the tube-heads. I is a door, which may be openedto sweep the fire-tubes and repair the boiler. The back connectionshould be sufficiently wide to permit a man to work at the tubes; or maybe provided with a door, the same as the front connection. Thetube-heads are made generally of cast-iron. The inner and outer shellsare connected by studs b 12, forming part of the same casting. To securegreat strength when the steam-pressure is very high we run bolts orrivets through the studs, or put in socket-bolts in the usual way. Thewater-tubes are secured in the inner plates of the tube-heads bycouplings Gr, one of which is shown separately in Fig. 5. This couplingconsists of a hollow cylinder or ring provided with screwthreads of thesame pitch on both its inner and outer surfaces, which threads extendnearly the whole length of the cylinder. At one end the opening in thecoupling is slightly reduced in size, and formed with six sides, or withany number of faces or projections, to fit an insidewrench. The couplingG screws into the rear sheet of the tube-head and on the exterior ofthe'tube at the same time, care being taken that the threads start thesame and are of the proper taper to insure a tight joint. Opposite theends of the tubes are hand-hole openings 0 c, of sufficient sizeto'permit the removal through them of the tubes A and couplings G. Theseopenings 0 c are closed by suitable bonnets or plugs d d, which, asrepresented, are

screwed into the outer plates of the tube-heads. The fire-tubes D D arearranged inside the water-tubes, and extend entirely through them acrossthe water-space in the tube-heads, and into the hand-hole bonnets (1,each tube and bonnet being preferably secured together by a screw havingthe same pitch as that on the exterior of the bonnet, so that thelatter, when it is put in, will screw into the tube-head and over thetube at the same time. The fronts of the bonnets d have annularprojections with flat faces thereon to receive a wrench.

When it is desired, one end of each tube A may be screwed directly intoa tubehead and the other end be secured with a coupling, as shown.

It is evident that the tube-heads for a large boiler may be made up ofany desired number of slabs or comparatively-narrow tube-headscontaining one or more rows of tubes, which slabs would be connectedtogether in the usual way.

By the use of the coupling G an injured tube can be readily removed fromany part of the boiler Without disturbing the j oints on the other tues.

We are aware that the pipe-fitters reducin g-socket bears someresemblance in appearance to our coupling Gr; but the former does not,on many sizes, have the threads on the outside and inside of the ring ofthe same pitch, and the threads taper to connect with pipes of differentsizes from opposite ends, which is diflerent from our device. Thecombination of our socket with a tube and tubehead is also new, andproduces a new, useful, and desirable result.

The fire-tubes D act as stays to the front sheets of the tube-heads, andgive great facilities for increasing the heating-surface of the boiler.They also enable us to conveniently carry the products of combustion onboth sides of the tube-heads, and we thereby utilize as heating-surfacewhat is cooling or radiating surface in many other boilers; also, thehigh temperatures on the two sides of the tube-heads entirely preventthem from being fractured by unequal expansion.

We claim as new and desire to secure by Letters Patent- Theconnecting-coupling G combined with a tube and tube-head, andconstructed with its opening adapted to an inside-wrench, substan tiallyin the manner shown and described.

PATRICK J. BRENNAN. QUINTIN M. QUIGG.

Witnesses W. H. WEIGHTMAN, OHAs. E. EMERY.

